Computer Aided Design

It could be the understatement of the year to say that CAD has changed the world of engineering product design, making it far easier to take a conceptual idea and refine it over and over again with ease. The effect of this revolution has, in a real sense, made it possible to nearly automate what has traditionally been the difficult and time-consuming portion of engineering drawing creation in much the same way that the word processing software has revolutionized the book writing and editing process. CAD systems have made it much easier to bring engineering ideas into the digital realm; engineers can analyse the fit-up of dozens of parts as well as the mechanical function of the complete working design before any real prototype is ever manufactured.

However, the CAD process has traditionally ended there. A design engineer would physically hand off a digitally created print or assembly drawing to the manufacturing engineer and then that individual would figure out how to best fabricate the part on the existing equipment and/or tooling that is currently available in the shop. While one potential advantage to this non-specific “hand-off” process is that the general prints created in this process can conceivably be adapted to any manufacturing process. Unfortunately, the flip side is that the design of the digital part and the print drawing and therefore the engineering drawings are never really optimized for the actual manufacturing operation that will probably ultimately be employed to create the physical part.

It is in this space where emerging Computer Aided Manufacturing (CAM) systems and technologies are really able to open up the true potential of digital CAD models in order to fully optimize the product design process, from the initial bud of an idea to the full-scale manufacturing of the production parts. This type of control system is commonly referred to as a complete “Product Lifecycle Management (PLM)” system. To back up a bit, a more detailed definition of CAM is required before the discussion can be sensibly continued because CAM is a relatively new technology, and many may not even be aware of its existence.

In short, CAM essentially refers to the use of computer software that is used to create the detailed blueprints (typically G-Code) to create the actual physical part, typically on some type of computer-controlled piece of industrial equipment - most commonly a CNC mill of some kind, but nowadays almost every kind of industrial manufacturing equipment employs numeric controls (NC) of some kind in order to perform a wide variety of manufacturing operations.

With this type of tool available, it’s really easy to see how advantageous it could be to employ both CAD/CAM tools concurrently, preferably during the earliest stages of the product lifecycle. With CAM software integrated (ideally) into the PLM management system, CAD models can be almost seamlessly translated into NC code for machines, and any manufacturing issues or potential speed bumps can be smoothed out during conceptual development of the part, long before the final design production drawing makes it to the manufacturing engineer who has potentially never seen the part drawing until that very minute.

Another benefit to the use of CAM software is that the final production (or prototype) part can be entirely built and controlled from the 3D digital CAD model, adding a level of production control to the process. From here, it’s easy to see why many are moving away from flat 2D printed drawings, and empowering the digital 3D model of the part to be the actual living “drawing” that controls all aspects of the production part because it can be fed directly into CAM software, rather than taking a flat 2D printed drawing and building the NC production instructions from a flat drawing. While this may not be feasible for all manufacturing processes and operations, it is becoming increasingly common for already wholly automated manufacturing processes or specific automated production operations.

There is nothing left to do now but to dive in and see which CAM software works for the users’ specific applications and functional requirements. For the really ambitious users, the introduction of CAM software may lead to the realization for a need for full-blown PLM systems to fully manage all aspects of part design and production. The following software is a great place to start to begin learning the basics of CAM software and systems: NX CAM, CAM Express, NX Tooling and Fixture Design, and Parasolid. A world of CA design and manufacturing awaits.